1110005991 has 8 divisors (see below), whose sum is σ = 1644453360. Its totient is φ = 740003976.

The previous prime is 1110005989. The next prime is 1110006043. The reversal of 1110005991 is 1995000111.

It is not a de Polignac number, because 1110005991 - 2¹ = 1110005989 is a prime.

It is a super-2 number, since 2×1110005991² = 2464226600111784162, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 41111333 = 1110005991 / (1 + 1 + 1 + 0 + 0 + 0 + 5 + 9 + 9 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1110005591) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20555640 + ... + 20555693.

It is an arithmetic number, because the mean of its divisors is an integer number (205556670).

Almost surely, 2^1110005991 is an apocalyptic number.

1110005991 is a deficient number, since it is larger than the sum of its proper divisors (534447369).

1110005991 is an equidigital number, since it uses as much as digits as its factorization.

1110005991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41111342 (or 41111336 counting only the distinct ones).

The product of its (nonzero) digits is 405, while the sum is 27.

The square root of 1110005991 is about 33316.7524077603. The cubic root of 1110005991 is about 1035.4006682301.

The spelling of 1110005991 in words is "one billion, one hundred ten million, five thousand, nine hundred ninety-one".